JP2022023644A - Radiation imaging panel, radiation imaging apparatus, radiation imaging system, method for manufacturing radiation imaging panel, and scintillator plate - Google Patents

Abstract

To provide a technique advantageous for improving an MTF in a radiation imaging panel.SOLUTION: A radiation imaging panel includes a substrate in which a plurality of pixels each including a photoelectric conversion element are arranged on a principal surface, a scintillator that includes a plurality of columnar crystals arranged on the principal surface, and a protective layer that includes a resin layer arranged to cover the scintillator. An area between the principal surface and a top face of the resin layer includes first areas that are areas between the adjacent columnar crystals of the plurality of columnar crystals, and a second area that is an area between the plurality of columnar crystals and the first areas and the top face and in which the resin layer is arranged. Particles of a metal compound are arranged in the first areas. The particles of the metal compound are arranged in the second area at a lower concentration than that of the first areas, or the particles of the metal compound are not arranged in the second area.SELECTED DRAWING: Figure 1

Description

The present invention relates to a radiation imaging panel, a radiation imaging device, a radiation imaging system, a method for manufacturing a radiation imaging panel, and a scintillator plate.

As a flat panel detector (FPD) used for radiography in medical image diagnosis and non-destructive inspection, an indirect conversion method that converts the radiation that has passed through the subject into light with a scintillator and detects the light emitted by the scintillator with a photoelectric conversion element. There is an FPD. For scintillators that convert radiation into light, columnar crystals of alkali metal halides such as cesium iodide are widely used in order to efficiently transmit the light converted from radiation to the photoelectric conversion element. Since the halogenated alkali metal compound is deteriorated by moisture absorption, a protective layer having a moisture-proof function may be arranged on the scintillator. Further, a reflection layer having a light reflection function may be arranged on the side opposite to the photoelectric conversion element of the scintillator so that the light converted from the radiation by the scintillator can be efficiently detected by the photoelectric conversion element. In Patent Document 1, a phosphor protective layer having a light reflection function and a moisture-proof function made of a resin containing light-reflecting fine particles is formed on the phosphor layer in a shape of being embedded between columns of columnar crystals of the phosphor. A radiation detector is shown.

Japanese Unexamined Patent Publication No. 2006-052980

There is room for study in the concentration distribution of the light-reflecting fine particles shown in Japanese Patent Application Laid-Open No. 1. Specifically, in order to improve the MTF (Modulation Transfer Function) between the columnar crystals of the scintillator, it is necessary that light-reflecting fine particles are arranged so that light does not enter the adjacent columnar crystals. There is. On the other hand, when the light-reflecting fine particles are present on the upper part of the columnar crystal, the light emitted upward from the columnar crystal of the scintillator is reflected by the light-reflecting fine particles and re-entered into the columnar crystal, thereby causing DQE (Detective Quantum efficiency). Can be improved. However, the light emitted upward from the columnar crystal may be diffused by the light-reflecting fine particles, and the effect of improving MTF may not be obtained.

An object of the present invention is to provide a technique advantageous for improving MTF in a radiation imaging panel.

In view of the above problems, the radiation imaging panel according to the embodiment of the present invention has a substrate on which a plurality of pixels including photoelectric conversion elements are arranged on the main surface and a plurality of columnar crystals arranged on the main surface. A radiation imaging panel comprising a scintillator comprising a scintillator and a protective layer including a resin layer arranged so as to cover the scintillator, wherein a region between the main surface and the upper surface of the resin layer is a plurality of the above. The first region, which is a region between the columnar crystals adjacent to each other of the columnar crystals, and the region between the plurality of columnar crystals and the first region and the upper surface, and the second region in which the resin layer is arranged. In the first region, particles of the metal compound are arranged, and in the second region, particles of the metal compound are arranged at a concentration lower than that of the first region, or the above. The second region is characterized in that the particles of the metal compound are not arranged.

By the above means, a technique advantageous for improving MTF in a radiation imaging panel is provided.

The cross-sectional view which shows the structural example of the radiation imaging panel which concerns on this embodiment. The figure which shows the structure of the radiation image pickup panel of FIG. The figure which shows the structure of the comparative example of the radiation imaging panel of FIG. The figure which shows the structure of the radiation image pickup panel of FIG. The figure which shows the structure of the comparative example of the radiation imaging panel of FIG. The figure which shows the characteristic of the radiation image pickup panel of FIG. The figure which shows the structural example of the radiation image pickup apparatus and the radiation image pickup system using the radiation image pickup panel of FIG.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. The following embodiments do not limit the invention according to the claims. Although a plurality of features are described in the embodiment, not all of the plurality of features are essential for the invention, and the plurality of features may be arbitrarily combined. Further, in the attached drawings, the same or similar configurations are given the same reference numbers, and duplicate explanations are omitted.

Further, the radiation in the present invention includes beams having the same or higher energy, for example, X, in addition to α rays, β rays, γ rays, etc., which are beams produced by particles (including photons) emitted by radiation decay. It can also include lines, particle rays, cosmic rays, etc.

The configuration and manufacturing method of the radiation imaging panel according to the present embodiment will be described with reference to FIGS. 1 to 7. FIG. 1 is a diagram showing a cross-sectional structure of the radiation imaging panel 100 in the present embodiment. The radiation imaging panel 100 includes a substrate 101 including a pixel region 110 in which a plurality of pixels including photoelectric conversion elements are arranged on the main surface 109, and a plurality of columnar crystals 102 arranged on the main surface 109 of the substrate 101. It includes a scintillator 107 including, and a protective layer 108 including a resin layer 103 arranged so as to cover the scintillator 107. A flattening layer 105 for alleviating a step due to a transistor, a wiring layer, or the like formed on the main surface 109 of the substrate 101 may be arranged between the substrate 101 and the scintillator 107.

A plurality of pixels may be arranged in a two-dimensional array in the pixel area 110. For example, 3300 × 2800 pixels are arranged on a 550 mm × 445 mm substrate 101. The 10 pixels arranged on the outer periphery of the 3300 × 2800 pixels may be a dummy pixel area, and the 3280 × 2780 pixels arranged inside the dummy pixels may form an effective pixel area of the pixel area 110. The number of pixels arranged in the pixel area 110 and the number of pixels arranged in the effective pixel area in the pixel area 110 may be appropriately set according to the size of the substrate 101, the image pickup target, and the like.

Further, in the pixel area 110 provided on the substrate 101, a column signal line for extracting a signal generated by each pixel and a row for driving each element including the pixels arranged in the pixel area 110. Signal lines etc. can be arranged. The column signal line and the row signal line can be electrically connected to the read circuit board, the drive circuit board, and the flexible wiring board, respectively. The board 101 may be provided with a connection terminal portion (not shown) in order to connect the column signal line and the row signal line to the read circuit board and the drive circuit board. The signal generated in each pixel of the pixel region 110 can be output from the radiation imaging panel 100 via the connection terminal portion.

Here, an example in which the read circuit and the drive circuit are arranged outside the radiation image pickup panel 100 is shown, but the read circuit and the drive circuit may be arranged in the radiation image pickup panel 100. Even in this case, a connection terminal portion (not shown) is arranged on the substrate 101, and the signal generated by each pixel of the pixel region 110 is transmitted through the connection terminal portion (not shown) to the radiation imaging panel 100. Can be output from.

In the present embodiment, the protective layer 108 includes a base 106 arranged on the side of the resin layer 103 opposite to the scintillator 107, and a metal layer arranged between the resin layer 103 and the base 106. .. For example, the protective layer 108 may be manufactured by forming an aluminum metal layer 104 on a base 106 and forming a resin layer 103 on the metal layer 104.

The scintillator 107 converts the radiation incident on the scintillator 107 into light that can be detected by the photoelectric conversion element provided on the substrate 101. For example, the scintillator 107 can convert radiation into visible light. As the scintillator 107, an alkali metal halide compound such as cesium iodide (CsI) on which columnar crystals grow can be used. When CsI is used as the scintillator 107, thallium iodide (TlI) can be used as the activator.

The scintillator 107 can be formed, for example, by using a thin-film deposition method. The substrate 101 is placed on a vapor deposition apparatus so that the flattening layer 105 is a vapor deposition surface, and CsI and TlI are filled in cell containers so that the Tl concentration is 1 mol% with respect to CsI, respectively, and co-deposited by heating. I do. As a result, the scintillator 107 including the plurality of columnar crystals 102 is formed.

A resin layer 103 is formed on the scintillator 107. The scintillator 107 composed of a plurality of columnar crystals 102 containing a halogenated alkali metal compound is deteriorated by moisture absorption. Therefore, the resin layer 103 may also function as a moisture-proof layer of the scintillator 107. Since the resin layer 103 covering the scintillator 107 has the function of a moisture-proof layer, it is possible to prevent the scintillator 107 from being deteriorated by moisture absorption.

FIG. 2A is an enlarged view of a portion 111 of FIG. A hot melt resin containing a polyolefin resin as a main component may be used for the resin layer 103. A hot melt resin is defined as an adhesive resin that does not contain water or a solvent and is solid at room temperature and is composed of a 100% non-volatile thermoplastic material (Thomas P. Flanagan, Adhesives Age, vol). 9., No. 3, pp. 28 (1966)). Further, the hot melt resin has a property of melting when the resin temperature rises and solidifying when the resin temperature decreases, and has adhesiveness to other organic materials and inorganic materials in a heated and melted state. On the contrary, it is a resin that is in a solid state at room temperature and has no adhesiveness. Further, since the hot melt resin does not contain a polar solvent, a solvent, and water, the scintillator 107 does not dissolve even if it comes into contact with the scintillator 107 having columnar crystals 102 of an alkali halide, so that it also has a function of a protective layer. Is possible.

As the hot melt resin, it is classified according to the type of the base polymer (base material) which is the main component, and polyolefin-based, polyester-based, polyamide-based and the like can be used. When a hot melt resin is used for the resin layer 103 as the protective layer 108 of the scintillator 107, it is important that the hot melt resin has high moisture resistance and high light transmittance through which visible light generated from the scintillator 107 is transmitted.

The material used for the resin layer 103 is not limited to the hot melt resin. For the resin layer 103, for example, a resin having a pressure-sensitive adhesive action due to an intermolecular force, that is, a resin called an adhesive material may be used. In this case, urethane resin or acrylic resin may be used as the resin layer 103. For example, as the resin layer 103, a polymethyl methacrylate resin among acrylic resins may be used.

The region between the main surface 109 of the substrate 101 and the upper surface 203 of the resin layer 103 shown in FIGS. 1 and 2A is defined as follows. The region between the adjacent columnar crystals 102 of the plurality of columnar crystals 102 of the scintillator 107 is referred to as the first region 211. The region between the plurality of columnar crystals 102 and the first region 211 and the upper surface 203 of the resin layer 103, and the region where the resin layer 103 is arranged is referred to as the second region 212. Here, the first region 211 is a region in which the ratio of the plurality of columnar crystals 102 of the scintillator 107 on the plane parallel to the main surface 109 of the substrate 101 is 75% or more and 98% or less. As shown in FIG. 2A, particles 201 of the metal compound are arranged in the first region 211.

FIG. 3 shows a cross-sectional view of the radiation imaging panel 300 of the comparative example. In the radiation imaging panel 300 of the comparative example, since the particles of the metal compound are not arranged in the first region 211, the light emitted by the columnar crystal 102 of the scintillator 107 can spread in the lateral direction of the drawing in the first region 211. .. As a result, by repeating reflection and refraction in the first region 211, the attenuation of light generated at the same time as the scattering of light is promoted, and the MTF may decrease.

On the other hand, in the present embodiment, as shown in FIG. 2A, particles 201 of the metal compound are arranged in the first region 211. By arranging the particles 201 of the metal compound, the light emitted from the columnar crystal 102 is more likely to be reflected by the columnar crystal 102 emitted again. As a result, the scattering of light in the first region 211 can be suppressed and the MTF can be improved.

The metal compound particles 201 may be metal oxide particles. For the metal compound particles 201, a material having a refractive index larger than that of the scintillator 107 can be used. For example, when the above-mentioned CsI (refractive index (n): 1.78 to 1.84 (depending on the type of activator, etc.)) is used as the scintillator 107 for the halogenated alkali metal compound, the refractive index is larger than that of CsI. Materials may be used. For example, the particles 201 of the metal compound include white lead (2PbCo _3.Pb (OH) ₂ ) (n: 1.94 to 2.09), zinc oxide (n: 2.0), and yttrium oxide (n: 1. 91), zinc oxide (n: 2.20), titanium oxide (n: 2.50 to 2.72) and the like can be used. For example, the refractive index of the metal compound particles 201 may be 1.94 or more and 2.72 or less. Further, for example, as the metal compound, particles of rutile-type titanium dioxide having a high refractive index among titanium oxides may be used.

Further, the metal compound particles 201 may have a higher refractive index than the resin constituting the resin layer 103. By increasing the difference between the refractive index of the metal compound particles 201 and the refractive index of the resin layer 103, light is easily reflected on the surface of the metal compound particles 201 in the first region 211. The refractive index of the hot melt resin described above is about 1.52, the refractive index of the urethane resin is about 1.49, and the refractive index of the acrylic resin is about 1.49 to 1.53.

Further, the average particle size of the metal compound particles 201 may be 200 nm or more and 500 nm or less. Generally, the sensitivity characteristic of a photoelectric conversion element is in the range of 500 nm to 800 nm, but since the effect of Rayleigh scattering appears if the particles are 1/2 or less of the wavelength of light, there is a high probability that the light will be reflected in the incident direction side. This is to become. For example, rutile-type titanium dioxide particles having an average particle size of 250 nm, a particle size distribution of 10% diameter D ₁₀ = 195 nm, a 50% diameter (median diameter) D ₅₀ = 245 nm, and a 90% diameter D ₉₀ = 275 nm are metal oxide particles. It may be used as 201.

In the configuration shown in FIG. 2A, a part of the resin layer 103 is arranged in the first region 211. Further, in the first region 211, the metal compound particles 201 are arranged in the resin layer 103. However, as shown in FIG. 2B, the resin layer 103 may not be arranged in the first region 211. Since the resin layer 103 is not arranged in the first region 211, the refractive index of the space (air layer) in the first region 211 becomes low. As a result, the difference in refractive index between the air layer and the columnar crystal 102 in the first region 211 becomes large, and it becomes difficult for light to be emitted from the columnar crystal 102. Further, the difference in refractive index between the air layer in the first region 211 and the particles of the metal compound particles 201 becomes large, and the light emitted from the columnar crystal 102 is more efficiently produced by the metal compound particles 201. Can be reflected in. This can further improve the MTF.

In the configuration shown in FIGS. 2 (a) and 2 (b), the metal compound particles 201 are not arranged in the second region 212. However, as shown in FIG. 4, particles 201 of the metal compound may be arranged in the second region 212. In this case, as shown in FIG. 4, the particles 201 of the metal compound may be dispersedly arranged in the portion of the resin layer 103 arranged in the second region 212.

Here, the concentration of the metal compound particles 201 arranged in the second region 212 with respect to the resin layer 103 will be considered. FIG. 4 shows the radiation imaging panel 100 of the present embodiment in which the particles 201 of the metal compound are added to the second region 212 at a concentration lower than that of the first region 211. FIG. 5 shows a radiation imaging panel 500 of a comparative example in which the concentration of the metal compound particles 201 in the second region 212 is equal to or higher than the concentration of the metal compound particles 201 arranged in the first region 211. .. When the concentration of the metal compound particles 201 is high in the second region 212, the resin layer 103 is scattered more in the film thickness direction (longitudinal direction in FIG. 5). Therefore, the amount of light returning to the columnar crystal 102 increases. However, the light reflected by the metal compound particles 201 arranged in the second region 212 may not be reflected by the columnar crystal 102 that emitted the light, but may be incident on another columnar crystal 102. .. That is, the light is diffused, which may cause a decrease in MTF.

FIG. 6 shows the MTF value at 2 lp / mm of the radiation imaging panel produced by changing the concentration of the metal compound particles 201 in the second region 212 in the resin layer 103. Since it is difficult to mix the particles 201 of the metal compound exceeding 90 vol% with the resin constituting the resin layer 103, the maximum concentration of the particles 201 of the metal compound in the resin layer 103 is 90 vol%. The MTF value was measured by irradiating X-rays according to the international standard radiation quality RQA5. Further, in FIG. 6, when the particles 201 of the metal compound are arranged in the first region 211 and the second region 212 at the same concentration (radiation imaging panel 500 of the comparative example), the second region 212 is the first. The case where the metal compound particles 201 are arranged at a concentration lower than that of the region 211 (radiation imaging panel 100 of the present embodiment) is shown.

As shown in FIG. 6, the radiation imaging panel 100 of the present embodiment in which the metal compound particles 201 are added to the second region 212 at a concentration lower than that of the first region 211 is the first region 211 and the first region 211. It can be seen that the MTF value is improved as compared with the radiation imaging panel 500 of the comparative example in which the particles 201 of the metal compound are added at the same concentration in the two regions 212.

Further, from FIG. 6, in the second region 212, increasing the concentration of the metal compound particles 201 in the resin layer 103 from 0 vol% improves the MTF, shows an optimum value at an appropriate concentration, and further increases the MTF. It turns out that it decreases. More specifically, in the second region 212, the MTF value is improved when the concentration of the metal compound particles 201 in the resin layer 103 is 0.15 vol% or more and less than 7.5 vol%. You can see that. When the concentration of the metal compound particles 201 in the second region 212 is low, the possibility of light reflected by the metal compound particles 201 in the second region 212 of the resin layer 103 is lower than when the concentration is high, and scattering occurs. It is suppressed. Further, due to the presence of an appropriate amount of the metal compound particles 201, the light reflected by the metal compound particles 201 is attenuated while being diffused and does not return to the columnar crystal 102. As a result, the radiation imaging panel 100 of the present embodiment can improve the MTF.

That is, as shown in FIG. 4, when the metal compound particles 201 are arranged in the second region 212, the metal compound particles 201 are arranged in the second region 212 at a concentration lower than that of the first region 211. It is good to have. This makes it possible to improve the MTF in the radiation imaging panel 100. Further, at this time, the concentration of the metal compound particles 201 of 212 in the second region in the resin layer 103 may be 0.15 vol% or more and less than 7.5 vol%. This makes it possible to further improve the MTF in the radiation imaging panel 100.

As described above, the metal compound particles 201 are arranged in the first region 211, and the metal compound particles 201 are arranged in the second region 212 at a concentration lower than that of the first region 211, or the second region 212 is arranged. When the particles 201 of the metal compound are not arranged in the two regions 212, the MTF can be improved. As a result, the radiation imaging panel 100 having high spatial resolution can be realized.

Next, a method for manufacturing the radiation imaging panel 100 in which the concentration of the metal compound particles 201 differs between the first region 211 and the second region 212 will be described. First, as the substrate 101, for example, 550 mm × 445 mm, 500 μm thick non-alkali glass is prepared. The substrate 101 is not limited to glass, and a resin substrate or a semiconductor substrate such as silicon may be used. A film forming step, a photolithography step, an etching step, and the like for forming a semiconductor layer such as silicon (for example, amorphous silicon) and a metal (for example, aluminum) constituting a wiring layer on a glass substrate 101 are repeatedly performed. As a result, the pixel region 110 is formed. In the pixel region 110, a plurality of pixels including an optical conversion element that generates an electric charge corresponding to the light emission of the scintillator 107 and a switching element that outputs a signal corresponding to the generated electric charge are arranged. Further, in the pixel region 110, a connection terminal portion (not shown) for driving the pixel and sending the obtained signal to an external circuit may be formed.

After forming the pixel region 110, an array inspection for checking the operation of the pixels formed in the pixel region 110 may be performed. After confirming that the operation is good by array inspection and that there are no or few missing pixels, the peripheral part of the substrate 101 is masked with a masking film for the purpose of protecting the connection terminal part (not shown) and flattened. The chemical layer 105 can be formed. The flattening layer 105 can be formed, for example, by placing the substrate 101 on a splace pin coater, spinning it at a rotation of about 100 rpm while spraying a polyimide solution, and then drying and annealing at a temperature of 220 ° C. .. For example, the flattening layer 105 may have a thickness of about 2 μm.

After preparing the substrate 101 on which the pixel region 110 is formed, the scintillator 107 is then formed. First, a vapor deposition mask is set in a region of the substrate 101 on which the flattening layer 105 is formed where the scintillator 107 is not formed, and then the substrate 101 is placed on the vapor deposition apparatus so that the flattening layer 105 serves as a vapor deposition surface. Then, CsI and TlI are each filled in a cell container so that the Tl concentration is 1 mol% with respect to CsI, and co-deposited by heating. The scintillator 107 may have, for example, a thickness of 380 μm and a film filling factor of 75%. At this time, the outer edge of the scintillator 107 may be arranged outside the outer edge of the pixel region 110. Further, when the scintillator 107 is vapor-deposited, the vapor deposition apparatus may be exhausted to ^10-3 Pa, and then heated with a lamp heater so that the substrate surface becomes 175 ° C.

After the scintillator 107 is formed, the metal compound particles 201 are sprayed from above the scintillator 107 so that the metal compound particles 201 enter between the columnar crystals 102 of the scintillator 107. Next, the radiation imaging panel 100 shown in FIG. 2B can be manufactured by placing a sheet of hot melt resin constituting the resin layer 103 on the scintillator 107 and laminating it using a vacuum thermal transfer device or the like. For example, first, the scintillator 107 and a sheet of hot melt resin are brought into contact with each other at 30 ° C., and then the pressure is reduced to 10 ^-1 Pa to remove air bubbles. Further, the substrate 101 on which the scintillator 107 is formed is formed by applying a pressure between the substrate 101 and the hot melt resin sheet constituting the resin layer 103, heating the substrate 101 to 70 to 100 ° C., and holding the scintillator 107 for an appropriate time. And the resin layer 103 constituting the protective layer 108 are bonded together.

Further, for example, after the scintillator 107 is formed, a portion of the resin layer 103 to be arranged in the first region 211 is applied by applying a resin to which the metal compound particles 201 are added so as to cover the scintillator 107. It may be formed. Next, a sheet of hot melt resin or a sheet containing a urethane resin or an acrylic resin called an adhesive having a pressure-sensitive adhesive action due to the above-mentioned intermolecular force is bonded onto a resin formed by a coating method. As a result, a portion of the resin layer 103 to be arranged in the second region 212 is formed. At this time, the metal compound particles 201 may be added to the resin bonded onto the resin formed by the coating method at a concentration lower than that of the resin formed by the coating method. As a result, the radiation imaging panel 100 shown in FIG. 4 can be manufactured. Further, the metal compound particles 201 may not be added to the resin bonded onto the resin formed by the coating method. As a result, the radiation imaging panel 100 shown in FIG. 2A can be manufactured.

The portion of the first region 211 of the resin layer 103 is not limited to being formed by the coating method. The portion of the resin layer 103 that is in contact with the columnar crystal 102 in the first region 211 may be formed by laminating a resin to which particles 201 of a metal compound are added by using a vacuum thermal transfer device or the like.

After forming the resin layer 103, a metal layer 104 such as aluminum or a base 106 may be formed on the resin layer 103. Further, in the above-mentioned hot melt resin sheet or sheet containing urethane resin or acrylic resin called an adhesive, a metal layer 104 such as aluminum is formed on a base 106, and a resin is formed on the metal layer 104. It may be produced by. A PET substrate or the like may be used for the base 106. For example, a metal layer 104 of aluminum having a thickness of 12 μm may be formed on a base 106 of a PET having a thickness of 30 μm, and a resin layer 103 or a part of the resin layer 103 may be formed on the metal layer 104. .. By laminating the resin layer 103 formed on the base 106 onto the scintillator 107, the radiation imaging panel 100 provided with the protective layer 108 shown in FIG. 1 can be manufactured.

Further, in the present embodiment, the case where the substrate 101 including the pixel region 110 in which a plurality of pixels are arranged is used has been described, but the present invention is not limited to this. For example, the substrate 101 may not include the pixel region 110. In this case, reference numeral 100 may be referred to as a scintillator plate. For example, by mounting this scintillator plate on a sensor substrate having a pixel region in which a plurality of pixels are arranged, it can function as a radiation imaging panel. Therefore, when the substrate 101 does not include the pixel region 110, the substrate 101 may be a transparent substrate that transmits the light emitted by the scintillator 107.

Hereinafter, a radiation imaging device incorporating the above-mentioned radiation imaging panel 100 and a radiation imaging system 800 using the radiation imaging device incorporating the radiation imaging panel 100 will be described with reference to FIG. 7.

The radiation imaging system 800 is configured to electrically image an optical image formed by radiation and obtain an electrical radiation image (that is, radiation image data). The radiation imaging system 800 includes, for example, a radiation imaging device 801, an exposure control unit 802, a radiation source 803, and a computer 804.

The radiation source 803 for irradiating the radiation image pickup apparatus 801 with radiation starts irradiation of radiation according to an exposure command from the exposure control unit 802. The radiation emitted from the radiation source 803 is applied to the radiation image pickup apparatus 801 through a subject (not shown). The radiation source 803 stops the radiation of radiation according to the stop command from the exposure control unit 802.

The radiation imaging apparatus 801 includes the above-mentioned radiation imaging panel 100, a control unit 805 for controlling the radiation imaging panel 100, and a signal processing unit 806 for processing a signal output from the radiation imaging panel 100. .. The signal processing unit 806 may, for example, perform A / D conversion of the signal output from the radiation imaging panel 100 and output it to the computer 804 as radiation image data. Further, the signal processing unit 806 may generate a stop signal for stopping the irradiation of radiation from the radiation source 803, for example, based on the signal output from the radiation imaging panel 100. The stop signal is supplied to the exposure control unit 802 via the computer 804, and the exposure control unit 802 sends a stop command to the radiation source 803 in response to the stop signal.

The control unit 805 is, for example, a PLD (abbreviation for Programmable Logic Device) such as FPGA (abbreviation for Field Programmable Gate Array), or an ASIC (Application Specific ASIC) general-purpose program, a general-purpose program, or an ASIC. It may consist of a computer or a combination of all or one of these.

Further, in the present embodiment, the signal processing unit 806 is arranged in the control unit 805 or is shown to be a part of the function of the control unit 805, but the present invention is not limited thereto. The control unit 805 and the signal processing unit 806 may have different configurations. Further, the signal processing unit 806 may be arranged separately from the radiation imaging device 801. For example, the computer 804 may have the function of the signal processing unit 806. Therefore, the signal processing unit 806 may be included in the radiation imaging system 800 as a signal processing device that processes the signal output from the radiation imaging device 801.

The computer 804 can control the radiation image pickup device 801 and the exposure control unit 802, and can perform processing for receiving the radiation image data from the radiation image pickup device 801 and displaying it as a radiation image. Further, the computer 804 can function as an input unit for inputting a condition for the user to capture a radiographic image.

As an example, the exposure control unit 802 has an exposure switch, and when the exposure switch is turned on by the user, it sends an exposure command to the radiation source 803 and also sends a start notification indicating the start of radiation to a computer. Send to 804. Upon receiving the start notification, the computer 804 notifies the control unit 805 of the radiation imaging apparatus 801 of the start of radiation irradiation in response to the start notification. In response to this, the control unit 805 generates a signal corresponding to the incident radiation in the radiation imaging panel 100.

The invention is not limited to the above embodiment, and various modifications and modifications can be made without departing from the spirit and scope of the invention. Therefore, a claim is attached to publicize the scope of the invention.

100: Radiation imaging panel, 101: Substrate, 102: Columnar crystal, 103: Resin layer, 107: Scintillator, 108: Protective layer, 109: Main surface, 201: Metal compound particles, 203: Top surface, 211: First region , 212: Second area

Claims (20)

Includes a substrate on which a plurality of pixels each including a photoelectric conversion element are arranged on a main surface, a scintillator containing a plurality of columnar crystals arranged on the main surface, and a resin layer arranged so as to cover the scintillator. A radiation imaging panel that includes a protective layer,
The region between the main surface and the upper surface of the resin layer is a first region which is a region between adjacent columnar crystals of the plurality of columnar crystals, and the plurality of columnar crystals and the first region and the said region. A region between the upper surface and a second region on which the resin layer is arranged, and includes.
Particles of the metal compound are arranged in the first region.
The second region is characterized in that particles of the metal compound are arranged at a concentration lower than that of the first region, or particles of the metal compound are not arranged in the second region. Radiation imaging panel. The radiation imaging panel according to claim 1, wherein the resin layer is not arranged in the first region. The radiation imaging panel according to claim 1, wherein a part of the resin layer is arranged in the first region. The second region, according to any one of claims 1 to 3, wherein the concentration of the particles of the metal compound in the resin layer is 0.15 vol% or more and less than 7.5 vol%. The radiation imaging panel described. The radiation imaging according to any one of claims 1 to 4, wherein the particles of the metal compound are dispersedly arranged in the portion of the resin layer arranged in the second region. panel. The radiation imaging panel according to any one of claims 1 to 5, wherein the refractive index of the particles of the metal compound is higher than the refractive index of the resin constituting the resin layer. The radiation imaging panel according to any one of claims 1 to 6, wherein the metal compound contains a metal oxide. The radiation imaging panel according to any one of claims 1 to 7, wherein the metal compound contains rutile-type titanium dioxide. The radiation imaging panel according to any one of claims 1 to 8, wherein the plurality of columnar crystals contain a halogenated alkali metal compound. One of claims 1 to 9, wherein the resin layer contains at least one of a resin made of a non-volatile thermoplastic material and a resin having a pressure-sensitive adhesive action by an intermolecular force. The radiation imaging panel described in section. Any of claims 1 to 10, wherein the first region is a region in which the ratio of the plurality of columnar crystals to a plane parallel to the main surface is 75% or more and 98% or less. The radiation imaging panel according to item 1. The radiation imaging panel according to any one of claims 1 to 11, wherein the average particle size of the particles is 200 nm or more and 500 nm or less. A base in which the protective layer is arranged on the side of the resin layer opposite to the scintillator, and
A metal layer arranged between the resin layer and the base,
The radiation imaging panel according to any one of claims 1 to 12, further comprising. The radiation imaging panel according to any one of claims 1 to 13.
A control unit for controlling the radiation imaging panel and
A radiation imaging apparatus comprising: The radiation imaging apparatus according to claim 14,
A signal processing device that processes the signal output from the radiation imaging device, and
A radiation imaging system characterized by including. A step of preparing a substrate in which a plurality of pixels including a photoelectric conversion element are arranged on a main surface and a scintillator containing a plurality of columnar crystals is arranged on the main surface.
A step of forming a first resin to which particles of a metal compound are added so as to cover the scintillator, and a step of forming the first resin.
A step of forming a second resin on the first resin is included.
The second resin is characterized in that particles of the metal compound are added at a concentration lower than that of the first resin, or particles of the metal compound are not added to the second resin. A method for manufacturing a radiation imaging panel. The first resin is formed by a coating method and is formed.
The method for manufacturing a radiation imaging panel according to claim 16, wherein the second resin is formed by bonding a sheet containing the second resin onto the first resin. The first resin is formed by laminating a sheet containing the first resin on the scintillator, and the second resin is formed by laminating a sheet containing the second resin on the first resin. The method for manufacturing a radiation imaging panel according to claim 16, wherein the radiation imaging panel is formed. A scintillator plate comprising a substrate, a scintillator containing a plurality of columnar crystals arranged on the main surface of the substrate, and a protective layer including a resin layer arranged so as to cover the scintillator.
The region between the main surface and the upper surface of the resin layer is a first region which is a region between adjacent columnar crystals of the plurality of columnar crystals, and the plurality of columnar crystals and the first region and the said region. A region between the upper surface and a second region on which the resin layer is arranged, and includes.
Particles of the metal compound are arranged in the first region.
The second region is characterized in that particles of the metal compound are arranged at a concentration lower than that of the first region, or particles of the metal compound are not arranged in the second region. Scintillator plate. The scintillator plate according to claim 19, wherein the substrate is a transparent substrate that transmits light emitted by the scintillator.

Images